The impact of COVID-19 on travel mobility of older passengers on Xi'an urban rail in China

The COVID-19 outbreak has led to unprecedented changes in people's lives and travel. Public transportation operators must understand individual mobility during COVID-19. Few studies have focused on the impact of COVID-19 on the travel behaviors of vulnerable older adults. To fill this research gap, this study is conducted using smartcard data from the Xi'an urban rail transit during the time of COVID-19 from February 1, 2020 to April 30, 2020. This study first divides the research objects, that is, passengers, into two groups of young adults and older adults, and periods into three stages: the outbreak, post-pandemic, and recovery. Indicators of travel distance, travel frequency, and activity duration were introduced for the two passenger groups to quantify their travel mobility in different stages. To evaluate the spatiotemporal performance of travel mobility, the travel time distribution of the two groups of passengers in each stage was continuously tracked and the returning passengers were proposed to measure the spatial distribution of station-level ridership. In summary, this study provides not only a deeper understanding of the mobility of older passengers during COVID-19 but also useful insights for urban rail transit managers to make more effective decisions for older adults.